Stop-charge current-regulator.



W. L. BLISS. STOP CHARGE CURRENT REGUL'ATOR. APPUCATION nuzb MAY 1, 1911. RENEWED APR. 6. m1.

1,246,854.. Patented Nov. 20, 1917.

UNITED STATES Plgp'ENtr OFFICE.

WILLIAM LNBLISS, 0F NIAGARA. FALLS, NEW YORK, ASSIGNOB, BY MESNE ASSIGN- MENTS, TO U. S. LIGHT & HEAT CORPORATION, O AGLR-A-FATALS .N'EW .YORK .A

COBJOR ATION OF NEW YORK.

STOP- CHARGE CURBENT-BEGU LATUR.

Specification of Letters Patent.

Patented Nov. 20, 1917.

Application filed Marl, 1911, Serial No. 624,479. RenewcdAPril 6, 1917. Serial No. 160,308.

regulator and tea system of electrical distribution' employing suclra regulator. Qne of the objects of the inv1ltiQ1l 1S to provide improved means for regulating to a constant value the current output of a generator, until a storage battery which is connected thereto is fully charged. Anotherobject is to provide a regulator which will d scon-' tinue the battery charging current afterthe battery voltage has risen a predeterm ned amount which will be sensitive and positive in operation, which .will besimple in construction and which will operate efliciently.

Certain broad features 'of i the invention herein disclosed are described and claimed in my co-pending -stop and-taper'chargc applications, Serial Nos. 624,109 and 624,110.

The drawings illustrate a prefci'red'form of regulator applied to a car lighting system in which a Tariable speed generator is employed. The regulator is adapted, of

l course, for use in other systems and may be embodied in various forms;

In the car lighting systcm 'illustrated, I

' provide a generator having an armature 1,

and a shunt field winding 2 having in series therewith two resistances 3 and 4, one of which is preferably greaterltl'ian' the other,

and. both of which arennormally short cir-' cuited The generator field resistance is' varied byrap'idly, making and'breaking theshort circuit'arouud tlise' resistances-This] 'ten s to rise above a operation iscon'trolled by two series wind? ings5 and 6 connected in the main. circuit.

Each winding or solenoid is provided witha core 7 and 8, the lower ends-of which are attached to pivoted levers 9 and 10 normally drawn up by springs 11 and 12. Spring 12 s preferably stronger than spring 11, and both springs may have theirtensions adusted by the adjustable nuts to which they are attached. Earl. of the cores 7 and 8 is of less ralue than the resistance 4.

adapted to vibrate rapidly, as hereinafter described, and each'carrics a contact member or electrode 13, 14, at its upper end adapted to coiiperate with corresponding fixed electrodes 15 and 16 to short circuit the corresponding resistances 3 and 4.

Auxiliary coils 17, 18 are connected in.

ing for the purpose of quickening the vibrationof the electrodes. A voltage responsive coil 19 is connected across the generator terminals and is adapted upon predetermined rise in the generator voltage, dueto an increase in the .counter-electromotive series with the generator shunt field winds force of the battery, to close the pivoted.

relay armi20 thereby connecting the voltage coils 21 and 22 in a shunt circuit across the} mains 23 and 24 and cutting down the batterv charging. current as hereinafter .de-

scribed.

The automatic switch 25 is adapted upon predetermined rise in voltage to connect the generator with the work circuit, comprising.

the battery 26 and the lamp circuit-27 arranged in parallel branches. Said switchalso disconnects the generator from the battery when the voltage of the former falls below that of the latter,

' The operation of the system is substantially as follows: \Vhen the generator is at rest, the automatic switch is open andthe closes. -This. occurs when the generator 'voltage'ls substantially equal too'r in excess of the battery voltage. The generator now charges the storage battery and carries 'the' lam load, if'any, 5 If tliegenerator-current f g V rrdctermined value the increased energlzatron of the SONGS coil 5 separates the short cn'clntmg-cont-acts 13 and 15 therebyintroducinginto the generator field circuit the resislanec 3.whieh is 'lhc'm creasod field resistance reduces the generator output and permits the spring 1.1 to raise the core and again short circuit the resistance ESQ This cycle. of opcraiion repeated rapidly so that the time lag in the field sistance 3 is introduced into circuit for successively longer intervals of time, whereby the effective value thereof is increased to offset the tendency toward an increase in the current delivered by the generator. Upon still further tendency of the enerator current to increase, the core 7 is h ld down by series winding Swhereby the resistance 3 is in circuit continuously, and the energization of the second series coil 6 becomes sulficient to overcome the pull of the stronger spring 12, whereby the core 8 is rapidly vibrated to introduce the larger resistance 4 intermittently into the generator circuit in addition to the resistance 3. The two resistances and the two sets of vibrating contacts are suflicient to confine the current under ordinary circumstances. It is ap parent, however, that a greater or ess number of resistances and short circuiting contacts may be provided, if desired, to meet varying requirements.

The auxiliary coils 17 and 18 assist the series coils 5 and 6 in opening the short circuit around the resistances thereby a0 celcrating the vibrations. These. coils are deenergized, however, as soon as the circuit is open' at the corresponding movable elec trode 13 or 14 thereby permitting the springs to return the respective cores quickly to a short circuiting position. Although I have disclosed one form of circuit connections for the auxiliary coils I do not desire to limit myself to said connections as the accelerated vibrations may be effected in other ways.

When the battery back voltage has risen to a predetermined value, it is desirable to discontinue the charging current and fur nish only sufficient current forthe'lamp load, if anyfexists. The pronounced rise in the counter-electromotive force .of the battery, which mayoccur when the same is almost fully charged, causes a corresponding'inerease in generator voltage whereupon the voltage coil 19 attracts the pivoted contact arm 20 and closes the shunt circuit through the voltage responsive coils 21 and associated with the respective cores 7 and 8. Inasmuch as the tendency ofeach resistance, vibi ating core and contact, is to co-act to maintain constant the number of ampere turns acting on said core, the'energization of said coils 2land 22 causes an immediate rcductionof the current in the series coils 5 and 6,.due to the increased resistance-of the generator field circuit. The gum-ruler current output is reduced almost to zero, it no lamps are in circuit. With a lamp load in circuit the current is reduced to substantially the value necessary to maintain the lamp load. The effect of the stop charge relay is to change the character of the regulation from current regulation to voltage regulation o r -to mixed current and voltage regulation with the 'voltage regulation predominating. The voltage coils 21 and 22 now control the character of the vibrations to maintain substantially constant the generator voltage.

If the speed of the generator armature is materially decreased so that the enerator voltage falls below the battery vo tage, the battery will discharge through the series winding of the automatic switch and open the same. Upon still further reduction in generator voltage, the stop charge relay opens the shunt circuit through the voltage coils 21 and 22.- If the generator speed should now increase again, the operation of the system will be the same as previously described. It should be noted that the stop charge relay coil 19 is connected between the generator and the automatic switch and not beyond said automatic switch. In the latter position said relay coil would be subjected to battery current after the automatic switch had opened, thereby preventing said relay from falling open at the proper time.

Where the generator armature is driven from a car axle, the direction of rotation thereof may be in either direction depending upon the direction of travel of thecar. Any suitable pole changing device (not shown) may be provided to maintain the proper polarity of the external circuit. This insures the charging of the storage battery in the proper direction.

It is apparent that various changes may be made in the structure and in the connections described, without departing from the spirit of the invention, andv I desire therefore, to cover broadly any suitable equivalent means for accom lishing the desired results and falling Witliin the scope of the appended claims.

I clalm as my invention- 1. In a car lighting system, a. variable speed generator having a shunt field winding, a main circuit extending therefrom, a resistance for regulating the field strength of the generator and connected in circuit with said winding, a pair of separable elec' trodes for controlling said resistance by rapidly short circuiting the same, a series electromagnetic winding arranged in said main circuit and operating said electrodes to cause the same to make and break contact, whereby the field strength of said generator is reduced as the output thereof tends to in-= crease, and a shunt electromagnetic winding connected across said circuit and adapted to operate said electrodes'to regulate said generator for substantially constant voltage upon predetermined voltage rise, the current regulation being substantially annulled when the voltage regulation becomes effective.

2. In a car lighting system, a variable speed generator having a shunt field winding, a plurality of resistances arranged in circuit. therewith, a plurality of pairs of separable electrodes connected in circuit with said resistances, one for each resistance, electromagnetic means connected in circuit in series with the armature of said generator and operating said electrodes to cause those to rapidly of each pairto make and break contact whereby the held strength of said generator is reduced as the-current delivered thereby tends to increase, and additional elcctro-.

magnetic means connected in a'shunt circuit and responsive to'a predetermined voltage rise of the system for substantially annulling the current regulationand substituting 3. In a car lightingsvstem, ahvariable .speetl generator having a shunt field winding, a main circuit extending therefrom, a

plurality of resistances of unequal values,

connected in said shunt field circuit, a plurality of pairs of separable electrodes connectcd in circuit to short circuit saidJe sistanccs, a plurality of clectromagnets adapted to respond to currents ofdifl'erent value and serving to cause said electrodes make ,and break contactsuccessively, said windings being arranged in said main circuit in series, whereby the field strength of the generator is reduced as the output of the generator tends to increase, a

plurality .of voltage responsive windings associated with said electrodes and adapted to vibrate the same to regulate the generator for constant voltage when the current responsive coils arein'ert, and voltage w sponsive means for connecting said volta responsive windings in circuit to annul 0 current regulation and substitute predominating voltage regulation therefor.

4. In a car lighting system, a variable speed generator, and a regulator therefor s'aid regulator including a resistafice adapted -to be connected in the generator field circuit, and a pair of separable electrodesQfor controlling saidresistance and a series windin responsive to the current dehvered by said generator and arranged to cause said electrodes to vibrate rapidly and make and break contact, whereby the field strength of the generator is reduced as the output thereof tends to increase, to maintain practically constant current, and a shunt winding also arranged to vibrate said electrodes to regulate the generator for. practically constant volta e, said seriesgwinding being mainly effective for regulating purposes below a certain predetermined voltage of the system, and said vol tage winding being cfl'ectlve for regulating purposes above said predetermined voltage.

5. A system of generation and regulation, includin a generator, and a regulator therefor, said regulator having a plurality of resistances adapted to be arranged in the lield circuit of the geueratm', a plurality of pairs of separable electrodes, one for each resistance, each pair of electrodes being connected iu-thc generator circuit to short circuit its' corresponding resistance when in contact, a plurality of series windings, one for each pair of electrodes, said series windings being responsive to generator current to vibrate said electrodes, whereby said genera-tor maintains constant current, a lurality of shunt windings, said shunt windings being responsive to generator voltage and adapted to vibrate said electrodes to regulate said generator for constant voltage,

the voltage regulation following the current regulation as the voltage of the system in-- creases.

6. A ca r lighting system including a generator, and a lrgulator therefor, said rcgula tor including a resistance adapted to be con erator for practically constant volta e and an auxiliary windin connected in said field circuit and in parallel withsaid resistance to modify said vibrations, said series winding being mainly effective for regulating purposes below a certain predetermined voltage of the system and said voltage winding being. effective for regulating purposes above said redet'ermined volta 7. A car lighting system inclu ing a variable source of current, and regulating means therefor,.said means including a vibratory regulating member, the means for operating said member including a-coil responsive to the current flowing rom said source, and a normally in'eflective coil responsive to the voltage of said source, said latter coil being brought into operation to afiect said vibratory member when a rcdetcrmined volta e of the source is reache 8. I n a car lighting system, a-variable speed generator, :1. storage battery to be charged thereby, and a regulator for said enc'rator, said regulator including a vibratmg contact controlling the field strength of the generator and operating means for said contact including a voltage coil for maintaining a constant potential on said system, and means for rendering said voltage coil inoperative upon a predetermined decrease in voltage of the system.

9. In a car lighting system, a variable s eed enerator, a storage battery to be eiargeg thereby,,and a, regulator for said generator, sai'd regulator ineludin a vibratory contact controlling the fiel strength of the generator, and operating means for said contact, including a, voltage coil for maintaining a constant potential on said system, means for rendering said voltage coil inoperative upon a predetermined decrease in voltage of the system, and a current responsive coil adapted upon a substantial increase in current to cause vibration of said contact to limit the maximum value of cur rent delivered by said generator.

10. In a, car lighting system, a variable speed enerator, a storage battery to be chargeg thereby, a vibratory regulator for said enerator, and operating means forsaid regu ator, said means including a current 0011 for operating said regulator upon a predetermined, maximum current being de livered by said generator, and voltage re sponsive means adapted under predetermined conditions to supersede said current coil in the regulation of said generator;

11. In a car lighting system, a variable s eed enerator, a storage battery to be c urge thereby, a vibratory regulator for Said enerator, and operating means for said regufiitor, said means including a current cell for operating said regulator upon a predetermined maximum current being delivered by said generator, voltage responsive means adapted under predetermined conditions to supersede said current coil ",1 the regulation of said generator, and means for determining the point at which said voltage responsive means shall become efl'ective to control the regulation.

12. In a car lighting system, a variable speed generator, a storage battery to be charged thereby, a vibratory regulator for said generator, and operating means for said regulator, said means in luding a current coil for operating said regulator upon a predetermined maximum eurrent being delivered by said generator, voltage responsive means adapted under predetermined conditions to supersede said current coil in the regulation of said generator, and a relay responsive to battery voltage for determining the point at which said voltage responsive means shall become effective to control the regulator.

13. Regulating means for a circuit, including a vibratory contact and operating means therefor, said means including a current responsive coil, and a normally inert voltage responsive coil, and means whereby said voltage responsive coil may be rendered active to exert its effect on the vibrations of said contact.

In witness whereof, I have hereunto subscribed my name in the presence of two witnesses.

WILLIAM L, BLISS. Vitnesses:

CAMPBELL C. CARPENTER, LAUREN A. PE'I'I'EBONE. 

